Shop by Make About Us Track Order
Contact Us
USA Flag
SUPPORT
SMALL BUSINESS
📦 My Cart
- OR -
Engine Control Module (ECM)
This photo shows the same type of part you'll receive. Since each used part has its own wear and scratches, yours may look slightly different. Check the product notes for details about the condition of this specific part.

2003 - 2005 BMW Z4 Engine Control Unit (ECU) (OEM)

Only 1 left in stock
$96.95

ℹ️ Product Notes

This is a used part. It is the main computer (ECU) that controls the engine. This part was tested and runs nicely. It fits vehicles without the high-performance package.

Match the part number on your old unit. This computer requires professional programming to your vehicle's VIN and keys to start the engine.

Original Part #(s): 12147508698, 12147510281, 12147510347, 7510347
Condition: Excellent (A)
Like new, minimal to no wear
159,449 miles
Odometer reading when part was removed
See Other BMW Z4 Engine Control Module (ECM)s
SKU #
3226471-A01295-095

Why Buy Used OEM Parts?

✓ Quality-Verified: Every used OEM part we sell has been professionally inspected and tested to ensure it meets our quality standards. While it may show some cosmetic wear from previous use, it's fully functional and ready to install.

✓ Original Equipment: This is a genuine OEM (Original Equipment Manufacturer) part - the exact same part that came with your vehicle from the factory. It's designed specifically for your make and model, ensuring perfect fitment and performance.

✓ Works Like New: Despite some visual wear, this part will perform just as well as a brand new one. The internal components and functionality are intact, giving you the same reliability you'd expect from OEM quality.

✓ Significant Savings: Save 50-80% compared to buying new! Used OEM parts offer exceptional value - you get factory quality at a fraction of the cost. It's the smart choice for budget-conscious vehicle owners who won't compromise on quality.

✓ Risk-Free Purchase: We stand behind our used parts with a generous 6-month warranty, 30-day returns, and 100% money-back guarantee. If it doesn't work out for any reason, simply return it for a full refund. You have nothing to lose!

🛡️ 30-Day Returns + 6-Month Warranty - Buy with Confidence!

Wrenchy the Robot

Meet Wrenchy - The Amazing Parts Assistant!Meet Wrenchy
The Amazing Assistant!

Let Wrenchy help you confirm if this is the right part.

Ask Wrenchy -
Type or Speak! 🎤

Vehicle Fitment Guide

This part fits the following vehicles:

BMW
Z4 2003-2005 (tapclick to expand)(tapclick to hide)
Swipe left/right to see more info
SubmodelSUB-
MODEL		 Body Style Years Engine Attributes
2.5i Convertible 2003 - 2005 L6 2.5L RWD | Automatic & Manual
3.0i Convertible 2003 - 2005 L6 3.0L RWD | Automatic & Manual
2004

⚠️ Important: Please verify your vehicle's year, make, model, and specifications before ordering. If you're unsure about fitment, contact our customer service team for assistance.

Policies

Shipping & Handling

  • Standard shipping: 3-7 business days via UPS Ground
  • Parts are carefully packaged to prevent damage during transit

Returns (30 Days)

We accept returns within 30 days of delivery for this part.

  • Defective parts: We will replace the part or issue a refund at our discretion
  • Electronic parts: Must be returned with the sealed inspection bag unopened. The clear bag allows full visual inspection before opening. Once opened, electronic parts can only be exchanged for a replacement if defective — no refunds
  • Programming: "Needs to be programmed to my vehicle" is not a valid return reason. Many modules require dealer programming — we're happy to help connect you with resources if your dealer says it's not programmable
  • Return shipping: We cover return shipping as part of our 100% money-back guarantee
  • Parts must be returned in original packaging and unmodified condition
  • Poorly packaged returns that arrive damaged will not be credited

6-Month Warranty

All used parts include a 6-month warranty from the date of purchase.

  • If your part fails within 6 months, we will send a replacement
  • Refunds are only issued if we cannot provide a suitable replacement
  • Warranty covers defects — not installation errors, misuse, or damage after installation

Note: Warranty is for replacement, not refund. A part failing on day 80? We'll replace it. But the return window for refunds is 30 days.

Damaged in Shipping?

If your part arrives damaged:

  • Stop immediately — do not install the part
  • Keep all original packaging and boxes
  • Take clear photos of the damage and packaging
  • Contact us within 48 hours of delivery

We will handle the carrier claim. You are not responsible for shipping damage — we just need your help documenting it.

Order Cancellation

Orders can be cancelled before shipment for a full refund. Once shipped, cancellations follow our return policy.

Symptoms & Diagnosis

Warning Signs of a Failing Engine Control Unit (ECU)

  • Check Engine Light is on
  • Engine misfires or runs rough
  • Engine stalls or won't start
  • Poor fuel economy
  • Failed emissions test
  • Transmission shifting problems
  • Erratic or unpredictable engine performance

How to Test if the ECU is the Problem

  1. Check the basics: Make sure the battery, spark plugs, fuel injectors, and wiring are all in good condition. A faulty ECU can mimic other problems.
  2. Scan for codes: Use an OBD-II scanner to read diagnostic trouble codes (DTCs). This can point to specific issues the ECU is detecting.
  3. Inspect the ECU: Look for any signs of physical damage, like corrosion, water damage, or burnt components.
  4. Test sensors and actuators: Use a multimeter to test the sensors and actuators that the ECU controls. If they are functioning properly, the ECU may be the issue.
  5. Consult a professional: A qualified mechanic can perform more advanced tests to diagnose ECU problems.

Common Failure Causes

  • Overheating
  • Water damage
  • Electrical surges
  • Vibration
  • Age and wear

Buyer's Checklist

What to Look For When Buying

  • Compatibility: Verify this ECU is designed for your specific vehicle year and model.
  • Condition: If buying used, look for a unit that has been tested and is guaranteed to be functional.
  • Warranty: Check if the part comes with a warranty.
  • Reputation: Buy from a reputable seller.

Quality Indicators

FeatureUsed OEMNew Aftermarket
OriginOriginal equipment manufacturer (OEM)Third-party manufacturer
TestingTypically tested and inspectedShould meet OE specifications
ReliabilityGenerally reliable, proven designVaries by manufacturer; can be reliable
PriceLowerCan be lower or comparable to used OEM

What's Typically Included

  • The Engine Control Unit (ECU) itself.
  • Sometimes, basic installation instructions.
  • Check with the seller to confirm what's included.

Installation Overview

Difficulty Level and Estimated Time

  • Difficulty: Medium
  • Estimated Time: 1-3 hours

Special Tools Needed

  • Basic hand tools (sockets, wrenches, screwdrivers)
  • OBD-II scanner
  • Multimeter (optional, for testing)

Critical Steps and Tips

  1. Disconnect the battery: This is crucial to prevent electrical damage.
  2. Locate the ECU: It's usually under the dashboard, under a seat, or in the engine compartment. Consult your vehicle's repair manual.
  3. Disconnect the wiring harness: Be careful not to damage the connectors.
  4. Remove the old ECU: Unbolt or unclip it from its mounting bracket.
  5. Install the new ECU: Connect the wiring harness and mount the ECU.
  6. Reconnect the battery:
  7. Clear any diagnostic trouble codes (DTCs): Use an OBD-II scanner.
  8. Check for proper operation: Start the engine and monitor its performance.

DIY or Professional Installation?

  • DIY is possible for mechanically inclined individuals with some experience.
  • Professional installation is recommended if you're not comfortable working with electrical components or if you lack the necessary tools.

Buying Options

Compare: Used OEM, New Aftermarket

FeatureUsed OEMNew Aftermarket
PriceGenerally the most affordable optionCan be comparable or slightly higher
ReliabilityProven reliability of the original partReliability can vary by manufacturer
QualityOriginal equipment qualityQuality depends on the aftermarket brand
WarrantyTypically comes with a limited warrantyWarranty varies by manufacturer and seller

Used OEM

  • Best value for genuine factory parts.
  • Tested and inspected to ensure proper function.
  • Significantly lower prices compared to new.

New Aftermarket

  • Brand new, third-party parts built to original equipment (OE) specifications.
  • Can be a good option if you prefer a new part.
  • Quality can vary, so choose a reputable brand.

Typical Lifespan

How Long This Part Normally Lasts

  • An ECU can last for the entire lifespan of the vehicle, often 10-15 years or more.

Factors That Affect Longevity

  • Operating temperature
  • Exposure to moisture
  • Electrical surges
  • Vehicle maintenance
  • Quality of the part

Price Ranges

Budget vs Mid-Range vs Premium Options

  • Used OEM: $150 - $350
  • New Aftermarket: $200 - $500

Labor Cost Considerations

  • Professional installation can cost $100 - $300, depending on the mechanic's hourly rate and the complexity of the job.

Total Job Cost Estimates

  • DIY (Used OEM): $150 - $350 (part only)
  • DIY (New Aftermarket): $200 - $500 (part only)
  • Professional Installation (Used OEM): $250 - $650 (part + labor)
  • Professional Installation (New Aftermarket): $300 - $800 (part + labor)

Vehicle-Specific Notes

Known Issues

  • Some models have issues with water intrusion affecting the ECU.
  • Check for any recalls or technical service bulletins (TSBs) related to the ECU.
  • Some owners have reported issues with the immobilizer system after replacing the ECU.

Verification After Install

How to Confirm Proper Operation

  • Start the engine and let it idle for a few minutes.
  • Check for any unusual noises or vibrations.
  • Monitor the engine's performance with an OBD-II scanner.
  • Take the vehicle for a test drive.

What to Look/Listen For

  • Smooth engine operation
  • No check engine light
  • Proper shifting (if applicable)
  • Normal fuel economy
  • Responsive acceleration

FAQ

Q: Will this ECU need to be programmed to my car?
A: It depends. Some ECUs may require programming or coding to match your vehicle's specific settings. Check with the seller or a qualified mechanic to confirm if programming is necessary.

Q: How do I know if this ECU is compatible with my car?
A: Verify the part is designed for your specific vehicle year and model.

Q: What if the ECU I receive is defective?
A: Buy from a seller that offers a warranty or return policy.

Q: Can I install this ECU myself?
A: Yes, if you have mechanical experience and the necessary tools. Otherwise, professional installation is recommended.

Q: What does the ECU control in my car?
A: The ECU controls many engine functions, including fuel injection, ignition timing, and emissions control.

Part Specifications

OEM Part Numbers:

  • BMW: 12147508698, 12147510281, 12147510347, 7510347

Fits Years: 2003 2004 2005

Why Millions Choose Go-Parts

Your Go-To Place for Auto Parts!

✅

6-Month Warranty

Shop with confidence and peace of mind

🏆

Trusted Since 2007

Over 19 years of excellence

🏅

OEM Quality

Meets or exceeds OE standards

🚚 Fast Shipping • ↩️ 30-Day Returns • 🎯 Perfect Fit Guaranteed

Racing Partner Videos

×

Search by Vehicle

1
2
3